package com.gzwh.v1.sysapi.shiro;

import com.auth0.jwt.JWT;
import com.auth0.jwt.interfaces.DecodedJWT;
import com.gzwh.v1.sysapi.core.LoginEnum;
import com.gzwh.v1.sysapi.core.jwt.JwtConfig;
import com.gzwh.v1.sysapi.core.jwt.JwtUtil;
import io.jsonwebtoken.Claims;
import org.apache.shiro.SecurityUtils;
import org.apache.shiro.ShiroException;
import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.AuthenticationToken;
import org.apache.shiro.subject.Subject;
import org.apache.shiro.web.filter.authc.BasicHttpAuthenticationFilter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.RequestMethod;

import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 登录验证拦截器
 * <p>
 * <p>
 * 时间：2019-07-14
 */
public class JWTFilter extends BasicHttpAuthenticationFilter {

    private Logger LOGGER = LoggerFactory.getLogger(this.getClass());
    @Autowired
    private JwtConfig jwtConfig;

    @Autowired
    private JwtUtil jwtUtil;

    /**
     * 判断用户是否想要登入。
     * 检测header里面是否包含Authorization字段即可
     */
    @Override
    protected boolean isLoginAttempt(ServletRequest request, ServletResponse response) {
        HttpServletRequest req = (HttpServletRequest) request;
        String authorization = req.getHeader("Authorization");
        return authorization != null;
    }

    /**
     *
     */
    @Override
    protected boolean executeLogin(ServletRequest request, ServletResponse response) throws Exception {
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        String authorization = httpServletRequest.getHeader("Authorization");
//        System.out.println("拦截器：" + authorization);
//        Claims claims = jwtUtil.parseJWT(authorization, jwtConfig.getSecret());
//        String name = claims.getSubject();

//        JWTToken token = new JWTToken(authorization);
        // 提交给realm进行登入，如果错误他会抛出异常并被捕获

//        token.setLoginType(LoginEnum.CUSTOMER.toString());
//        try {
//            getSubject(request, response).login(token);
//            // 如果没有抛出异常则代表登入成功，返回true
//        }catch (Exception e){
//            System.out.println("fasheng"+e.getMessage());
//        }


        try {
            DecodedJWT jwt = JWT.decode(authorization);
//            System.out.println("拦截器：用户名:" + jwt.getClaim("username").asString());
//            System.out.println("拦截器：密码:" + jwt.getClaim("password").asString());
//            System.out.println("拦截器：登录标识:" + jwt.getClaim("uid").asString());
            CustomerAuthenticationToken token = new CustomerAuthenticationToken(jwt.getClaim("username").asString(),
                    jwt.getClaim("password").asString(), false);
//            System.out.println("tongg");
            token.setLoginType(jwt.getClaim("uid").asString());
            token.setLoginForm(authorization);
            getSubject(request, response).login(token);
        } catch (Exception e) {
            System.out.println("132");
            return false;


        }
        return true;
    }

    /**
     * 这里我们详细说明下为什么最终返回的都是true，即允许访问
     * 例如我们提供一个地址 GET /article
     * 登入用户和游客看到的内容是不同的
     * 如果在这里返回了false，请求会被直接拦截，用户看不到任何东西
     * 所以我们在这里返回true，Controller中可以通过 subject.isAuthenticated() 来判断用户是否登入
     * 如果有些资源只有登入用户才能访问，我们只需要在方法上面加上 @RequiresAuthentication 注解即可
     * 但是这样做有一个缺点，就是不能够对GET,POST等请求进行分别过滤鉴权(因为我们重写了官方的方法)，但实际上对应用影响不大
     */
    @Override
    protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) {
        if (isLoginAttempt(request, response)) {
            try {
                executeLogin(request, response);

            } catch (Exception e) {
                response401(request, response);
            }
        }
        return true;
    }

    /**
     * 对跨域提供支持
     */
    @Override
    protected boolean preHandle(ServletRequest request, ServletResponse response) throws Exception {

        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        HttpServletResponse httpServletResponse = (HttpServletResponse) response;
        httpServletResponse.setHeader("Access-control-Allow-Origin", httpServletRequest.getHeader("Origin"));
        httpServletResponse.setHeader("Access-Control-Allow-Methods", "GET,POST,OPTIONS,PUT,DELETE");
        httpServletResponse.setHeader("Access-Control-Allow-Headers", httpServletRequest.getHeader("Access-Control-Request-Headers"));
        // 跨域时会首先发送一个option请求，这里我们给option请求直接返回正常状态
        if (httpServletRequest.getMethod().equals(RequestMethod.OPTIONS.name())) {
            httpServletResponse.setStatus(HttpStatus.OK.value());
            return false;
        }
        return super.preHandle(request, response);
    }

    /**
     * 将非法请求跳转到 /401
     */
    private void response401(ServletRequest req, ServletResponse resp) {
        try {
            HttpServletResponse httpServletResponse = (HttpServletResponse) resp;
            httpServletResponse.sendRedirect("/401");
        } catch (IOException e) {
            LOGGER.error(e.getMessage());
        }
    }
}
